/*
* Copyright (c) Microsoft Corporation. All rights reserved.
* Copyright (c) 2023 Huawei Device Co., Ltd.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This file has been modified by Huawei to verify type inference by adding verification statements.
*/

// === tests/cases/compiler/optionalTupleElementsAndUndefined.ts ===
declare function AssertType(value:any, type:string):void;
// Repro from #50753

type UnNullify<T> = { [K in keyof T]: NonNullable<T[K]> };

type Foo = UnNullify<[a: 1, b?: 2 | undefined]>;

type Test = [a: 1, b?: 2] extends Foo ? true : false;  // true

// Types in the following declarations should be identical

let v: [1, 2?];
AssertType(v, "[1, (union)?]");

let v: [1, (2 | undefined)?];
AssertType(v, "[1, (union)?]");

let v: [a: 1, b?: 2];
AssertType(v, "[1, (union)?]");

let v: [a: 1, b?: 2 | undefined];
AssertType(v, "[1, (union)?]");

let v: UnNullify<[1, 2?]>;
AssertType(v, "[1, (union)?]");

let v: UnNullify<[1, (2 | undefined)?]>;
AssertType(v, "[1, (union)?]");

let v: UnNullify<[a: 1, b?: 2]>;
AssertType(v, "[1, (union)?]");

let v: UnNullify<[a: 1, b?: 2 | undefined]>;
AssertType(v, "[1, (union)?]");


